This invention relates to plant container liners and a method of manufacturing plant container liners or blanks therefor. In particular, although not exclusively, the invention relates to a method of forming sphagnum moss liners for plant containers such as hanging baskets, especially those baskets in the form of skeletal containers. While the specification refers primarily to the use of sphagnum moss, the principles of the invention may be extended to other vegetative fibre materials such as coconut fibre.
Because of its unique water retaining properties, and pleasant appearance as a natural plant substance, sphagnum moss has traditionally been a favoured material for use in conjunction with floral arrangements and related horticultural activities.
Traditionally, sphagnum moss has been sold mostly in a dried state but sometimes in a wet state, but generally in a natural loose form in which each filament of the moss plant is separate and distinguishable.
In recent decades, a new technology has developed in the sphagnum moss industry. This is the use of pressure to compress the loose moss in a press into compact sheet form. These sheets are of various thickness, usually from 2 or 3 mm to about 7 mm. They are somewhat like cardboard in flexibility and look somewhat like particle board in texture.
In its traditional loose form, sphagnum moss has always been associated with hanging baskets. One reason for this is its particular ability to absorb and retain water up to and exceeding 20 times its own weight. Another is its natural and aesthetically pleasing appearance.
The most common traditional method of using sphagnum moss to line hanging baskets is to place some loose moss in the bottom of a wire hanging basket, then cover the moss with a little potting mix. After this the basket is gradually filled, firstly by building up the outer layer of sphagnum moss around the outside of the basket and secondly by holding it in place with a little more soil and potting mix. This process is repeated several times until the lining of sphagnum moss reaches right to the upper rim of the hanging basket.
This is obviously a very labour intensive task. For this reason it has mostly been performed at home by the enthusiastic gardener, and by staff in some garden centres. In this form, hanging baskets with a layer of sphagnum moss directly inside the wire basket can be made available only when they are filled with soil and potting mix, because it is the soil and potting mix which holds the outer lining of loose filaments of moss in place.
It is evident that there is an extremely limited scope for selling sphagnum moss lined hanging baskets in this form. The labour content in filling them is very high. In addition the basket would need to be regularly watered to keep the potting mix and the sphagnum moss moist.
For these reasons, sphagnum lined hanging baskets filled in this way would normally have to be made and sold in the same garden centre. Such articles could not be manufactured on a large scale using technology and production machinery and then transported in bulk nationally and internationally to many retail outlets. Consequently only very small numbers of such sphagnum lined baskets are made up in this way.
One company in USA has taken a step forward in this regard and created a sphagnum moss lined hanging basket which can much more readily be transported in cartons as freight, or even posted in the mail, which makes them much more marketable than the previously mentioned type. In these, filaments of loose dry sphagnum moss are fixed onto the outside of the basket with very fine filament or wire. This means that no soil or potting mix is needed to hold the sphagnum moss in place.
However, the process of sewing the filaments or moss onto the outside of the basket is very time consuming and keeps this type of moss lining within the category of a hand crafted item. As such, this type of liner will always be relatively expensive, limited in numbers, and therefore a speciality item.
One New Zealand company also markets a product shaped like a Maltese cross. When placed inside a hanging basket, the edges fold up and contour to the shape of the basket. A disadvantage of a liner in this form is that initially at least, the liner does not conform satisfactorily to the shape of the curved hanging basket.
Common features of known compact sphagnum liners are:
1 They are both presented to the public in flat, one dimensional form.
2 Both must be placed inside a hanging basket before they can assume and retain the three dimensional shape of the basket.
3 Both are in untreated compacted sheet form and bear little resemblance to sphagnum moss.
4 Both have to be assembled by the purchaser according to instructions supplied.
Extensive market research conducted on our behalf concerning basket liners made up of flat sections of compacted sphagnum moss shows that unless there has been a considerable amount of prior instruction and education, a large proportion of the general public and the gardening public are not aware that:
such flat shaped pieces of compacted sphagnum moss are in fact basket liners;
such a smooth surfaced, cardboard-like substance is in fact sphagnum moss.
In addition, the public needs instruction as to how such objects should be assembled into their end form as basket liners.
Consequently, expensive and extensive advertising and promotional material, and special training of shop sales persons at every point of sale has been necessary to combat the fact that many people do not know:
what such objects are and what they are for;
what they are made of;
how they are to be assembled.
In spite of all this instruction, which does increase the price unnecessarily, many people still pass them by because they do not know what they are, and do not realise how they make up into a basket liner.
As a result, these liners have been observed in sales outlets being progressively moved into obscure positions of display where they gather dust.
Moreover, the known forms of hanging basket liners will not retain moisture indefinitely and much moisture from the soil will be expirated through the liner. Furthermore, hanging basket liners formed of natural material will have a tendency to grow mould on the other surface thereof which reduces the visual appeal of the hanging baskets. Thus there has been a tendency to use the less aesthetically pleasing and less environmentally friendly plastic containers.
It is an object of the present invention to provide a plant container liner or a blank therefor, and a method of manufacturing a plant container liner/blank which will address at least some of the foregoing problems or at least provide the public with a useful choice over liners/blanks at present available.
Accordingly, in accordance with a first aspect of the present invention, there is provided a method of forming a plant container liner or a blank therefor, the method including: forming a first layer of compressed sphagnum moss which is dry or at least partially dried; and incorporating a layer of water resistant material into the liner or blank.
In a preferred form of the invention using sphagnum moss, the moss is compressed into a sheet which when reconstituted will incorporate the layer of water resistant material. It would be desirable for the layer of water resistant material to be sandwiched within the sphagnum moss but towards the outer surface of the liner because for visual impact, concealment of the water resistant layer by a layer of sphagnum moss is desirable. This can be achieved by initially laying a thin layer of the sphagnum moss, then the water resistant layer and finally the major amount of sphagnum moss to be compressed.
It is also intended that a wide range of materials may be utilised to form the water resistant or water impervious layer. In a simple form the layer can be provided by a mat of cellulous material such as a suitable grade of paper which may or may not have surface coatings. Suitable surface coatings where provided can facilitate adhesion to the sphagnum moss and increase the water retentive characteristics of the layer.
A suitable plastic sheet may replace the sheet of cellulous material with the surface of the sheet being treated to facilitate adhesion to the sphagnum moss if desired. Aluminium foil is another desirable alternative. It may be possible to create a mechanical bond between the foil and the sphagnum moss as a consequence of deformation of the foil in association with the sphagnum moss during compression or by using a special form of foil which has surface characteristics that will enhance mechanical bonding.
In a yet further modification, the water resistant layer can be provided by treating a section of the sphagnum moss with a suitable chemical mixture so that upon heat and pressure, or pressure alone, a layer of the sphagnum moss sheet will assume characteristics resisting water penetration. For example, a plastics compound which at ambient temperatures would be in liquid form could be sprayed onto the sphagnum moss and which when subjected to heat and pressure, or pressure alone forms the required water resistant layer.
The compounds which can be used in this way are wide ranging and include thermo setting plastics material that can be applied in a liquid form. The end use to which the compressed sheet is applied would influence the material selected. For example, a layer created by tar, or a tar paper or other tar-like material would be a possibility. Cost, visual appearance and the end use to which the sheet is to be put, will all influence the selection of the material which will form the water resistant barrier.
In accordance with a second aspect of the invention, there is provided a plant container liner or a blank therefor, the liner or blank having a first layer of compressed sphagnum moss which is dry or at least partially dried such that it is reconstitutable, with a water resistant layer incorporated into the liner or blank.
Any of the features mentioned above in connection with the first aspect may be applied to the second aspect.
Accordingly in a further aspect of the invention, there is provided a sheet of processed sphagnum moss including a first layer of sphagnum moss which is dry or at least partially dried such that it is reconstitutable and a second layer of compressed sphagnum moss which is dry or at least partially dried and a water resistant layer provided between the two layers of plant material.
In accordance with yet another aspect of the present invention, there is provided a blank for a plant container liner including a base section and a unitary arcuate section associated with the base section, the arcuate section being adapted to fold about the base section to form a continuous wall in the 3 dimensional form of the liner.
It has been found that with this construction, the expansion of the moss as it absorbs water tends to close the joints thereby providing joint seals which retain the moisture but still allow a sufficient drainage to avoid stagnation problems within the plant container.
Each blank is generally of a form including a circular base section and an arcuate wall section extending around the circular base. In this way, the wall section defines a continuous wall around the circular base in the assembled form of the liner. In one form of such a blank the base section may be integrally formed with the wall section along a part of the periphery of the base, allowing the remainder of the wall section to be folded about the remainder of periphery of the base. The blank may be secured in the three dimensional form by overlapping extension areas of the base and/or the wall section and by joining together the ends of the wall section by fastening means such as staples passing through the overlapped extension areas. Where the blank is made directly in the aforementioned shape by the use of a mould, the outline of the recess of the mould suitably defines this shape.
In another form of the invention, there is provided a blank for a plant container liner including: a substantially semi-circular base section having a substantially semi-circular edge; and one or more wall sections adapted to fold about the arcuate or semi-circular edge of the base section to form with the base section, a surrounding wall in the 3 dimensional form of the liner wherein at least one of the wall sections is integrally formed with the base section along a part of the edge of the base section and is adapted to follow the contour of the semi-circular edge of the base section in the 3 dimensional form of the liner, dimensional form of the liner.
It will be appreciated that a liner of this form will be appropriate for use in a wall mounted hanging basket.
In accordance with a further aspect of the present invention, there is provided a packaged liner for a plant container, the liner being of three dimensional form with a top opening and one or more walls extending in an upstanding configuration towards the opening, the liner including one or more sheets of reconstitutable compressed sphagnum moss secured in the three dimensional form of the liner, wherein the sphagnum moss is partially reconstituted such that the wall(s) of the liner retain sufficient stiffness to be self-supporting in the upstanding configuration, the liner being enclosed in a sealed package.
Any of the liners or blanks described in the foregoing aspects of the invention may be provided with or without a water resistant layer/barrier. The barrier may be provided by a sheet of paper of suitable composition preferably having a suitable adhesive such as a PVA applied to each surface. However it is emphasised that the barrier can be provided by any suitable sheet of material, for example, a sheet of plastics material. The material may itself be a composite or layered material, for example, paper with a more impervious material provided, for example, by some waterproof substance within the paper. A wide variety of materials is intended to be encompassed within this application.
The sphagnum moss may be compressed into individual sheets (in the form of blanks), each for folding into an individual liner. An appropriately shaped mould may be used to form each of the blanks. Mould loading devices may be utilised to load a predetermined quantity of moss into the recesses of the moulds.
Alternatively, the sphagnum moss may be compressed into the form of a larger sheet so that a number of blanks may be cut from the sheet and each blank folded to form a three dimensional liner.
Some additional advantages may be realised using a water resistant layer/barrier as discussed previously. Any suitable water barrier can be incorporated and it is desirable for the water barrier to be towards the outer layer of the compressed sphagnum moss.
One form of the water barrier can be provided as an aluminium foil. In this case a small thickness of compressed sphagnum moss will be attached to what will form the outer side of the completed liner and a thicker layer of compressed sphagnum moss attached to the inner side of the aluminium foil. In the method of manufacture, the layer of aluminium foil would be placed upon a prelaid bed of sphagnum moss and a second layer of sphagnum moss placed on the foil prior to compaction. The adhesion between the sphagnum moss and foil can be created using a suitable adhesive coated onto the foil but the invention is intended to encompass any suitable means of creating a bonding between the foil and the sphagnum moss.
It may be possible to create a mechanical bond between the foil and the sphagnum moss as a consequence of deformation of the foil in association with the sphagnum moss during compression or by using a special form of foil which has surface characteristics that will enhance mechanical bonding.
It is also possible within the ambit of the present invention to provide a liner which has different water retentive characteristics. For example, in the base section and a lower part of the wall there could be a water resistant layer but in the upper section of the wall the water resistant layer may not be included.
The blanks or liners described in the foregoing aspects may be comprised of moss which is preferably pre-dried to around 18 to 20 percent moisture by weight prior to compaction into sheets. In a preferred form of the invention, the moss is compressed without any additional heat being applied. However, in countries (eg Australia) which exclude the import of any moss other than that which is certifiably free of viable seed, the moisture content of the sphagnum moss prior to the compaction may be greater to generate steam during hot-pressing to sterilise the moss. See for example New Zealand Patent Specification 314613/314825. Australian Patent Specification 6037/98 or Chile Patent Specification 1790-98, the contents of which are incorporated herein by reference. However, where possible, the cold-press method is preferred because it is believed that hot-pressing slows the rate at which the compressed sphagnum moss can be reconstituted.
For transportation it is clearly desirable to ensure that the three dimensional form of the liners are able to be nested one within the other to minimise the transportation space required in sending the liners to the point of sale outlets.
The blanks or liners described in the foregoing aspects may be comprised of moss which is preferably pre-dried to around 18 to 20 percent moisture by weight prior to compaction into sheets. In a preferred form of the invention, the moss is compressed without any additional heat being applied. However, in countries (e.g., Australia) which exclude the import of any moss other than that which is certifiably free of viable seed, the moisture content of the sphagnum moss prior to the compaction may be greater to generate steam during hot-pressing to sterilise the moss. See for example New Zealand Patent Specification 314613/314825, Australian Patent Specification 60637/98 or Chile Patent Specification 790/98, the contents of which are incorporated herein by reference. However, where possible, the cold-press method is preferred because it is believed that hot-pressing slows the rate at which the compressed sphagnum moss can be reconstituted.
In accordance with yet another aspect of the present invention, there is provided a method of forming a liner for a plant container, the liner being of three dimensional form with a top opening and one or more walls extending in an upstanding configuration towards the opening, the method including: assembling one or more sheets of reconstitutable compressed sphagnum moss into the three dimensional form of the liner; securing the sheet(s) in that form wherein the sphagnum moss is partially reconstituted such that the wall(s) of the liner retain sufficient stiffness to be self-supporting in the upstanding configuration.
The invention of assembling this compressed plant liner in a three dimensional form in our factory, (ie remote from the point of retail sale) so that it can be transported and presented in the market in this manner, makes possible the further advantage that the manufacturer can also at least partially reconstitute the surface of at least a portion of the liner, preferably by spraying the outer surface with a suitable quantity of fine water spray so that the outer surface swells up to such measure that it appears to any uninformed person as in fact being made of sphagnum moss. It is anticipated that a liner in this form will have a very instant and widespread appeal. However, the invention is not limited to partial reconstitution being performed in our factory. This step may be effected at a point of retail sale.
The degree of reconstitution of the outer surface should necessarily be limited, lest the liner soak up too much water, thereby losing its self-supporting quality and become bulky and heavy. The quantity of water for an average sized liner would be between 10 and 15 ml.
The partial reconstitution may be effected prior to or after assembling the blank to the three dimensional form. This may be achieved by spraying the liner with a suitable liquid such as water. The liquid might be coloured (eg green) to contribute a pleasing aesthetic effect to the liner. Where the liner has a base and upstanding walls, the partial reconstitution is preferably effected on the exterior of the walls. In a most preferred form of the invention, the partial reconstitution is effected to the whole exterior of the liner.
The present invention can attain some additional advantages by using a water retentive barrier within the sphagnum moss sheet. Any suitable water retentive barrier can be incorporated and it is desirable for the water retentive barrier to be disposed towards the exterior of the three dimensional liner. This will assist with the partial reconstitution. If water is sprayed onto the exterior of the three dimensional liner, then only the sphagnum moss in an outer surface layer at the exterior of the liner will reconstitute leaving the greater thickness of compressed sphagnum moss on the inside of the water retentive barrier unaffected by any moisture used for the reconstitution of the outer surface.
The present invention provides a method of manufacture for a plant liner which will ensure that at the point of sale, the purchaser is able to readily recognise that the three dimensional liner is formed as a compressed sphagnum moss liner.
In accordance with another aspect of the invention, there is provided a method of packaging liners formed according to the method set out above, the method including: enveloping a single liner or a plurality of nested liners with shrink wrapping material such that the shrink wrapping material extends into the interior of the or the top liner, weighting the shrink wrapping material with a weight placed in the interior of the or the top liner; and heat treating the shrink wrapping material to conform to the shape of the liner.
The invention consists in the foregoing and also envisages construction of which the following give examples only.